Currently available hair cutting devices, typically have a hair cutting body with an electric motor powering cutting knives for cutting the hair of a person or a pet. The hair length after cutting is generally determined through proper selection of interchangeable comb unit defining the distance between the skin and the cutting knives.
For user convenience, some hair cutting devices allow for the comb unit to be moved so that the hair length can be changed within a hair length range that is supported by the particular comb unit.
In addition to allowing for such movement of the comb unit relative to the cutting knives, the hair cutting device disclosed by WO 2006/134576 provides a graphical indication of the hair length to the user by means of a hair length indicator comprising a fixed delimiter and movable delimiters that move together with the comb unit when the comb unit is moved.
In the hair cutting device according to WO 2006/134576, the comb unit that is attached to the hair cutting device interacts with a lever that is mechanically coupled with the movable delimiters to move these in a circumferential direction when the lever is actuated. Only one of the movable delimiters at a time is visible to the user through a transparent window. By selectively activating levers on opposite sides (left and right) of the comb unit, two different movable delimiters can be displayed to the user depending on which comb unit is used, so that the hair length that is indicated to the user is adapted to the comb unit that is currently mounted on the hair cutting device.
Although the hair cutting device according to WO 2006/134576 gives the user proper information about the currently set hair length, there still appears to be room for improvements, for example in respect of the reliability of the hair cutting device.